mozilla-b2g/gaia — pull request #2167 by steveck-chung (2012-07-04 03:28:01+00:00)
Title: Fix the day separator header lost issue and gjslint.

Because changing the unread tag in conversation list view will force to update messages again and redraw the list, _lastHeader need to reset before query and update the list in the second pass. So I delete _lastHeader after the list append to view.

BTW, please modify the lastHeader to latestHeaderDate or something more recognisable wording for readability and check gjslint error before commit, thanks :)